1. Technical Field
The present disclosure relates generally to a control circuit for a fan motor and a method of controlling the same, and more particularly to a modularized control circuit with a signal-capturing function for a fan motor and a method of controlling the same.
2. Description of Related Art
For applications of the fan motor, a pulse-width modulation (PWM) technology is usually used to control speed, output power, and so forth of the fan motor. Because of different structures of the motor as well as various loads driven by the motor, the external PWM signal needs to be adjusted to drive and control the rotor of the motor according to practical conditions.
For the signal process of controlling the motor, the digital-to-analog conversion or the low-pass filtering are used to convert the pulse control signal into an analog voltage signal. Afterward, the analog voltage signal is processed by a control logic circuit or a microprocessor with an analog-to-digital function. However, it is easily to cause errors of capturing the frequency or the duty cycle of the pulse control signal because of the limitations of sensitivity of the low-pass filter or the digital-to-analog converter. In addition, a counter is usually used for count operations. Also, the normal operation of the counter is that one access action is executed in one triggering operation thereof. However, the triggering time needs to be increased if the counter has to execute consecutive access action. But, for this reason, it is easily to increase the error risk of setting the trigging time.
Accordingly, it is desirable to provide a modularized control circuit with a signal-capturing function for a fan motor and a method of controlling the same to increase the reliability and convenience of replacement of the control circuit for the fan motor by providing parameter setup via the software, firmware, and the hardware.